Winsor & Newton - Gloss Varnish - 75 ml - Artisan Gloss Varnish is a water based varnish which does not contain any hazardous solvents. The varnish provides finished paintings with protection from dirt and grease and when dirty itself, can be removed with Artisan Varnish Remover. Artisan paintings should be allowed to dry completely before varnishing, at least 6-12 months for thin films, longer for impasto paintings. Varnishes should not be used within the paintings as mediums.